\\[-1.8ex] Soil Heterogeneity & $-$0.125$^{***}$ & $-$0.058$^{**}$ & $-$0.057$^{**}$ & $-$0.055$^{**}$ & $-$0.060$^{**}$ & $-$0.060$^{**}$ \\ 
  & (0.041) & (0.026) & (0.026) & (0.026) & (0.025) & (0.025) \\ 
\\[-1.8ex] 
Observations & 80,887 & 80,887 & 80,887 & 80,887 & 80,887 & 80,884 \\ 
R$^{2}$ & 0.001 & 0.227 & 0.228 & 0.228 & 0.228 & 0.229 \\ 
